Not even a baby could interfere with Gennady Golovkin's training for his middleweight title fight with Canelo Alvarez.

Golovkin was getting ready to put the final touches on his training camp last week in the mountains of southern California when word came from Los Angeles that his wife was going into labour with their second child.

Trainer Abel Sanchez urged him to go to the hospital, but Golovkin was not about to interrupt preparations for what could be the defining fight of his career.

"He said, 'Coach, the baby is going to come whether I'm there or not. I have to train'," Sanchez said.

The baby did come as Golovkin was wrapping up his training session in Big Bear. He was able to be with his wife and newborn daughter the next day, though he declined to answer questions about the birth.

There were plenty of boxing questions to keep the Kazakh occupied as he met with a contingent of media to talk about a fight that many in boxing are already comparing to the great middleweight clashes of the past.

The former Olympic silver medallist and Mexico's biggest boxing star meet on Sunday (AEST) in a battle that has been years in the making.

Golovkin preparing for 'street fight'

For Golovkin the fight is a chance to finally break out as a superstar outside the core of boxing fans who believe he is that already in the ring, but it is also shaping up as the toughest fight of his career, one that leaves no room for distractions, baby or not.

"It's not a game, it's a fight," Golovkin said.

"You can go back home or go to the hospital. It's dangerous and everyone understands that."

Golovkin was in a jovial mood while meeting with reporters, something Sanchez attributed both to becoming a father for the second time and knowing the biggest fight of his career is only days away. He laughed easily, made a few jokes and talked about what he expected from a fighter he has been pursuing for more than two years.

"It's not an easy fight for him or me. I think the second half will be crazy, like a street fight," Golovkin said.

The fight matches a big puncher in Golovkin, who has 33 knockouts in winning all 37 of his fights, against Alvarez, whose only loss in 51 fights came against Mayweather.

Boxing purists have salivated over the matchup in styles, with Golovkin always coming forward and Alvarez being a devastating counter-puncher.

"The styles have the ingredients to make a fight that can go down in history for many years," Alvarez said through an interpreter.

The expectations have helped the fight gain traction, despite coming just three weeks after Mayweather and McGregor met. That fight attracted more than 4 million pay-per-view subscriptions, driven mostly by the curious and UFC fans.